Sieve analysis of some commercial fluid cokes



Reissued June 3, 1969 26,597 CEMENTITIOUS SYSTEMS Augustus B. Small,Brussels, Belgium, and Henry Nash Babcock, Old Greenwich, Conn.,assignors to Esso Research and Engineering Company, a corporation ofDelaware No Drawing. Original No. 3,234,035, dated Feb. 8, 1966, Ser.No. 282,217, May 22, 1963. Application for reissue Jan. 12, 1968, Ser.No. 698,985

Int. Cl. C04h 7/02 US. Cl. 106-89 19 Claims Matter enclosed in heavybrackets II] appears in the original patent but forms no part of thisreissue specification; matter printed in italics indicates the additionsmade by reissue.

ABSTRACT OF THE DISCLOSURE Portland cement shrinkage is controlled oreliminated by incorporating fluid cake in the cement compositions.Improved control is achieved over that obtained using conventionalaluminum or iron shrinkage-counteracting materials.

This invention relates to improved cementitious systems and moreparticularly to concrete systems. More specifically, it relates to theuse of a material which will control the shrinkage of a cementitioussystem without seriously degrading the strength of the final structure.

A great variety of cementitious systems or materials are in common usetoday. Perhaps the best known and most widely used of these materials iscement, particularly Portland cement. Portland cement is a tan to blackpowder manufactured by mixing and grinding a calcareous material such aslimestone or chalk with an argillaceous material, i.e., clay. Themixture is then heated in an oven to about l3501800 C. at which timevitrification takes place. The clinker produced is pulverized, mixedwith 2% gypsum, and ground to 200 mesh. Usually when used for concrete,1 part of cement is mixed with 2 parts of fine aggregate, such as sandand 4 parts of a coarse aggregate such as gravel including crushed rockand stones. About six gallons of water are needed for each 100 pounds ofcement.

Other commonly used cementitious materials include grout: a mixture ofcement, water and fine aggregate, that is to say. aggregate which willpass through a No. 4 sieve. Mortar is also in wide use as a cementitiousmaterial; this contains cement, lime, fine aggregate and water. Somewhatless commonly used is topping: a mixture of cement, fine aggregate andcoarse aggregate. Fine aggregate includes sand and mineral particles ofabout 9 maximum diameter which pass through mesh. Coarse aggregateincludes mineral particles larger than including all gravels and largerstones and crushed rocks. Other cementitious materials exist but nopurpose would be served by merely listing them.

All of these cementitious materials have a common shortcoming; uponsetting or curing the mass of the material is subjected to shrinkage.Shrinkage of concrete presents problems of design, long-term behavior,methods of reinforcement and over-all utility. Since concrete is theonly inorganic thermosetting plastic which has been available to thebuilder at an attractive price, methods have been found to design aroundthe shortcomings of concrete. Materials to counteract the shrinkage ofconcrete have been on the market for many years. Foremost among them arealuminum powders and the use of iron filings. Aluminum powder causesexpansion by the formation of hydrogen which in turn forms minute voidsin the concrete. By balancing the hydrogen release with the anticipatedshrinkage of the mass, a nonshrinking concrete can be produced. With thealuminum powder technique, very careful control at all stages ofconcrete preparation is essential to yield the desired result. One ofthe problems is the need to measure and thoroughly mix very smallquantities of aluminum powder under field conditions and by unskilledlabor. In fact, a fraction of an ounce must be mixed for every ton ofconcrete.

Iron filings are used as a shrink counteracting material because as theiron rusts it expands, the expansion takes place during setting.However, this presents serious difficulties since the rusting maycontinue long after the desired time. This is particularly true if theconcrete involved is directly exposed to outside weather conditions.With iron filings a temporary shrinkage occurs. After this the shrinkageof cement is counteracted by internal expansion during curing.

According to this invention, it has been found that the addition of arelatively small amount of fluid coke, that is to say coke recoveredfrom the fluid coking of petroleum, to cement mixes will cause thesystem to expand during the setting rather than shrink. Expansion occursbetween the initial and final set.

By controlling the amount of coke used, the cement system can beregulated to give a cement mass that neither shrinks nor expands andhence a non-shrinking Portland cement mixture can be produced.

The advantages of this discovery are apparent. The problems of levelcontrol as well as stresses and strains imposed by a shrinking systemare virtually eliminated The shrinkage of the cementitious system iscontrolled by replacing a portion of the sand or fine aggregate withfluid coke. About 15 to by volume of coke replacing sand in a systemcontaining .1 to 2 weights Portland cement, to 2 to 4 weights fineaggregate to 2 to 5 weights of coarse aggregate will yield a system thatis essentially of constant volume during cure. All or part of the fineaggregate may be replaced by fluid coke. The amount of fluid coke addedto cement mixes, such as Portland cement, coarse aggregate and fineaggregate may be between 0 to 100 wt. percent of the fine aggregatedepending on the degree of expansion desired.

Still further advantages result from the lower density of the cementsystem or mixture. Coke has a bulk density of about lbs/cu. ft. and areal density of about 92 lbs/cu. ft. By contrast, sand has a bulkdensity of about lbs/cu. ft. and a real density of about lbs/cu. it.

This ability to expand Portland cement in a controlled manner is limitedexclusively to fluid coke; no other type of coke or carbon has thiselfect. It should be noted that coal clinkers may also cause expansionbut in a harmful and uncontrolled amount. In the clinker case, theexpansion is related to the sulfur content.

The behavior of fluid coke in cementitious systems is believed to be dueto its inherent ability to adsorb small amounts of inert gases which canbe released by the heat generated by the setting concrete.

There has recently been developed an improved process known as the fluidcoking process for the production of fluid coke and the thermalconversion of heavy hydrocarbon oils to lighter fractions. See Pfeifferet al. Patent 2,881,130 granted Apr. 7, 1959. The fluid coking unitconsists basically of a reaction vessel or coker and a heater or burnervessel. In a typical operation the heavy oil to be processed is injectedinto the reaction vessel containing a dense turbulent fluidized bed ofhot inert solid particles, preferably coke particles. A transfer line orstaged reactors can be employed. Uniform temperature exits in the fluidcoking bed. Uniform mixing in the bed results in virtually isothermalconditions and effects instantaneous distribution of the feed stock.

In the reaction zone the feed stock is partially vaporized and partiallycracked. Product vapors are removed from the coking vessel and sent to afractionator for the recovery of gas and light distillates therefrom.Any heavy bottoms are usually returned to the coking vessel. The cokeproduced in the process remains in the bed coated on the solidparticles. Stripping steam is injected into the stripper to remove oilfrom the coke particles prior to the passage of the coke to the burner.

The heat for carrying out the endothermic coking reaction is generatedin the heater or burner vessel, usually but not necessarily separate. Astream of coke is transferred from the reactor to the burner vessel,such as a transfer line or fluid bed burner, employing a standpipe andriser system; air being supplied to the riser for conveying the solidsto the burner. Sufficient coke or other carbonaceous matter is burned inthe burning vessel with an oxygen-containing gas to bring the solidstherein up to a temperature suflicient to maintain the system in heatbalance.

The burner solids are maintained at a higher temperature than the solidsin the reactor. About of the coke, based on the feed, is normally burnedfor this purpose. This may amount to approximately to 30% of the cakemade in the process. The unburned portion of the coke represents the netcoke formed in the process and is partially recycled to the reactor, theremainder being withdrawn.

Heavy hydrocarbon oil feeds suitable for the coking process includeheavy crudes, atmospheric and crude vacuum bottoms, pitch, asphalt,other heavy hydrocarbon petroleum residue or mixtures thereof. Typicallysuch feeds can have an initial boiling point of about 700 F. or higher,an A.P.I. gravity of about 0 to and a Conradson carbon residue contentof about 5 to 40 wt. percent. (As to Conradson carbon residue seeA.S.T.M. Test D-180-52.)

It is preferred to operate with solids having a particle size rangingbetween 100 and 1000 microns in diameter with a preferred averageparticle size range between 150 and 400 microns. Preferably not morethan 5% has a particle size below about 75 microns, since smallparticles tend to agglomerate or are swept out of the system with thegases. The withdrawn product coke has a diameter predominantly in therange of about 20 to 200 mesh, i.e., about 80 to 95 weight percent.

It is preferred to use fluid coke in the size range of great variety ofpurposes such as the making of bricks, blocks, floors and walls as wellas reinforced concrete structures.

Of particular interest in the manufacture of a plastic composition whichmay be utilized in the production of cement blocks. The plasticcomposition would consist of about 1 part by weight of Portland cementin admixture with between .1 to 4 parts by weight of fine aggregate.Coarse aggregate would be present in an amount between about 1 and 6parts by weight, water is added in the amount of .3 to 1.0 part byweight and fluid coke in the amount of .1 to 3 parts by weight. Thefluid coke is preferably of a dimension so that 100% passes through a 20mesh screen, but all mesh sizes are usable from commercial fluid cokers.However, no coke particles should be larger than This mixture is placedin a plastic mold to harden, the mold being of any desired shape and atthe end of 24 hours a cement block is removed. The process may bespeeded up by using additives which increase the cure rate of concreteutilizing an injection process, the setting time will be a smallfraction of a minute.

In order to obtain a substantially nonshrinking mixture, fluid coke inthe amount of 10 to 20 wt. percent of the fine aggregate should beadded. The fluid coke would represent about 25 to 35 wt. percent basedon the amount of Portland cement in the mixture. Although no definiteupper limit to the size of fluid coke particles need be set, it ishighly desirable to work with fluid coke which is under in size.

Since the coke cementitious mass expands against the mold, themanufactured block will have excellent dimensional stability-a factor ofgreat importance in its use in construction.

The following experiments were carried out by making mixtures ofcementitious materials. The Portland cement, coarse aggregate, fineaggregate and fluid coke mixture was mixed with water. The order ofmixing did not have an effect on the outcome; some of the various mixingtechniques will be described in detail.

The mixtures were stirred in a cement mixer and poured into a cylinderwhich was 36" high and 1" in diameter; the shrinkage, expansion orconstant size of the mixture was then observed.

In all of the following tables the term sack refers to 95 lbs. ofmaterial. The fine aggregate used was sharp, clean Ottawa sand. In allexperiments green fluid coke was the source of fluid coke.

TABLE I.FLUID COKE CAUSES EXPANSION System Composition, Pts. By Wt.Change in Cast Cylinder Water Bleeding,

Height I I11.

Exp. No. Remarks Fluid Inches Percent Coke 20 Send Portland Water 1 Day1 Wk.

Mesh b Cement 1 Day 1 Wk. 1 Day 1 Wk.

1 1. 6 1. 0 0. 86 +1. +1. 50 +4. 2 +4. 2 0. 88 0. 75 Coke plus waterplus cement.

2 1.6 1. 0 0. 86 -0. 75 -0. 75 -2. 1 2. 1 None None Evacuated coke at100 F. for 1 hr. to 1 p.s.i.a. Then added water to break vacuum. Wetcoke used.

3 1.6 1. 0 0. 86 +1. 50 +1- 50 +4- 2 +4.2 0. 75 0. 63 Eylaguated gake,exposed overnight e ore use.

4 3 1. 0 0. 86 0. 3B 0- 63 1. 1 l.8 0.25 None Sand volume equal to cokevolume in other experiments.

of cementitious mass.

about 100% through 20 mesh but any size up to 5 will producesatisfactory results.

The coke used may be either green fluid coke or calcined fluid coke. Fora description of green fluid coke see British Patent No. 819,588. Thecementitious matehe ooke was spread so that maximum contact with theatmosphere would take place.

Table I illustrates the expansive eflect produced by fluid coke inadmixture with cement. The order of addition does not influence thebehavior of the fluid coke. In Exp. 1, the coke and cement were mixedtogether and the water was added to complete the formulation. In

rials described in this invention may be utilized for a Exp. 2, the cokeand water were mixed and then the cewater and, in view of the resultswith fluid coke, it might be expected that excessive expansion wouldtake place. Not only did no expansion take place, but the systems shrank0.25 inch.

Delayed coke has a chemical composition very close to fluid coke, yetdelayed coke did not produce expansion but behaved in the same inertmanner that sand does.

TABLE III.SYSTEM COMPOSITION PARTS BY WEIGHT 0% Coke Coke 50% Coke 100%Coke 100% Coke 7-Day Strength (Compression) 2,827 p.s.i...- 3,427p.s.i.... 2,100 p.s.i...- 601 p.s.i-

675 p.s.i. 28-Day Strength (Oompression).- 4.151p.s.i..-. 4,875p.s.i.... 2,739 p.s.i-..- 742 p.s 1.. 813 p.s.i. Dens1ty(I,bs./C.F.) 146145..." 137 120 116. l-Day Height Change None..- None. +1 -5is'.Coke/Cement Ratio (Lbs./Sack) 66.25.- 132.58 132.68. Water/Cement Ratio(Gai./Saek) 6%.... 6 6. Coke/Water Ratio (Lbs/Gal.) 10.00.- 22.11 22.11.Sand/Cement Ratio (Lbs/Suck).-." 222 194.5 111 NOTES In the cgmpositionsin Table III, it is obvious that the water/cement ratio is about 0gaL/IOO pounds 0! eemen Percent Coke indicates the percent of sandvolume replaced by coke.

age of 0.75 inch. In Exp. 3 the coke was again evacuated but this timewas exposed overnight; at atmospheric pressure and as a result airbecome re-entrained inthe coke. The coke caused expansion in thePortland cement mixture. In the final experiment (Exp. 4) no coke wasused; the filler or fine aggregate was sand exclusively. Consequentlyafter a day, a shrinkage of 0.38 inch took place and after one week itwas 0.63 inch.

The set cement mixtures containing fluid coke, sand, aggregate andPortland cement were off-white in color.

The behavior of the evacuated coke indicates that the ability of fluidcoke to counteract the shrinkage of cementitious systems during cure isdue to the surprising property of being able to desorb normally heldgases under curing conditions. This is especially surprising since nobubbling occurs, nor are objectionable voids formed in the cementitiousmass. The exact mechanism is not known but it appears to be a controlleddesorption.

Table III illustrates the eflect of varying the amount of fluid coke tobe added to sand-cement mixtures. At 0% fluid coke there is considerableshrinkage; between 15% and fluid coke by volume of the fine aggregateresults in a mixture which essentially does not shrink nor expand. Aconcentration of 100% coke (no sand) causes distinct expansion. As forstrength, 15% fluid coke actually produces a stronger material than 0%fluid coke (100% sand or fine aggregate). At 50% fluid coke there is adecrease in strength. However, the cement is still satisfactory for mostpurposes. At 100% fluid coke the strength is reduced to 675 p.s.i.

This reduction in strength at 100% fluid coke may be remedied byutilizing a mixture of fluid and delayed coke as in Table IV.

l High shrinkage results from low volume of sand used. b 100% through a320 mesh screen (-44 microns).

Table II is a comparison of the effects of fluid coke versus delayedcoke, carbon black and sand. For a description of delayed coke seeNelson et a1. Patent 2,835,- 605, granted May 20, 1958.

As illustrated by Table II, the fluid coke used in Exps. 1, 2, 3, 4 and6 produced an expansion. In Exp. 6 the expansion was less and this wasdue to the fact that the fluid coke and delayed coke togetherrepresented 1.6 parts by weight. The delayed coke used in Exp. 5resulted in shrinkage. In the same fashion, the carbon black of Exp. 7and the sand of Exp. 8 both resulted in shrinkage.

The failure of carbon black to cause expansion is rather surprising.Carbon black is known to be a highly surface active material. Carbonblack is readily wet by TABLE IV.-SYSTEM COMPOSITION PARTS BY WEIGHTExperiment 1 NOTES:

5% indicates 34 ounce Dares air ontraining agent/gal. of water. Percentcoke indicates the percent oi sand volume.

Table IV illustrates the eflects on expansion and strength of adding toa cement mixture 100% fluid coke in contrast to a 100% coke mixturecomprising 50% fluid coke and 50% delayed coke.

In Experiment 1 a mixture of delayed coke and fluid coke was utilized.Seven-day strength was 3357 psi. and 28-da strength was 4063 p.s.i.

In Experiment 2 the fine aggregate was replaced entirely by fluid coke.This mixture was considerably weaker: seven-day strength was 707 psi.and 28-day strength was reduced to 353 psi.

Mixtures of to 70% fluid coke and to 85% delayed coke may also beemployed.

As one would expect from the above, other cementitious systems such astopping, grout and mortar may also be made essentially nonsbrinking.This may be accomand only a slight loss in strength. By contrast, a1-day height change of minus A inch resulted when no fluid coke wasadded.

Coke behavior correlates closely with the total noncernent components inthe formulations. In the above Table V, the use of coke represents about16 vol. percent of the non-cement components and the system isnonshrinking.

Table VI illustrates the effects of adding fluid coke to grount. Theaddition of %6 part of fluid coke resulted in a grout which produced noshrinkage at all. Grout with no fluid coke added had a 1-day heightchange of minus A inch. The strength of the grout increased with theaddition of the V part fluid coke.

The increase in strength with relatively small portions of fluid coke isprobably due to the fine fluid coke filling in the crevices between thelarger sand particles. How- TABLE VL-GROU'I Coke/Cement Ratio (LbsJSack).

Water/Cement Ratio (GalJ Sack a n4 a 5%. Coke/Water Ratio (LbsJGaL) 2.5410.37 19.22.

Sand/Cement Ratio (Lbs.l

Sack) Norms:

grotup dgsi nation 195 indicates proportion by volume oi cement andsand.

or s cc e The mixture was confined by sealing ofl the ends oi thecylinder.

plished by replacing about 15 to 50% by volume of the fine aggregatecontent of either topping, grout or mortar with fluid coke. The exactamount of fluid coke to be utilized will vary somewhat with the otheringredients of the cementitious system.

dieates the divers port one 0! sand replaced by coke on a volume basis.

ever, in spite of the potentially better packed fine aggregate thesystem still was capable of expanding. As the concentration of fluidcoke is increased the fluid coke takes over a larger portion of thedirect load. The loss in strength at 1% parts fluid coke is probably dueto the excessive quantity of fines. Sand with too much fine coke giveslower strength systems.

TABLE TIL-MO RTAR Group Designation 1-1-6 0 Parts Coke to Part Coke 1Part Coke 7-Day Strength (Compression) 28-Day Strength (Compression;-Day Strength (Compression Density (Lbs./C.F.)

Coke/Water Ratio (Lbs./Gal.) Sand/Cement Ratio (Lbs/Sack) 31s p.s.i. 49sp.s.i.

NOTES! Group desi Parts coke ndloates the divers portions of sandreplaced by coke on a volume has ations 1-1-6 indicate proportions oicement, lime and send, by volumle. s.

The mixes were batched in a laboratory and suificient water was addedfor workability.

TABLE V.TOPPING Group Designation 1-2-4 0 Parts Coke 1 Part Coke 2,456p.s.i-. 3,886 1.8.1--.

Norse:

Group designation 1-2-4 indicates proportions by volume of cement,

sand and blue stone. Parts coke indicates the portions oi sand replacedby coke by volume,

Table V indicates that the effect of fluid coke on topping, anothercementitious material, is the same as concrete.

In Table VII mortar was utilized. As expected, the height change with nofluid coke added was negative. With /2 part fluid coke there was noheight change. One part fluid coke resulted in a slight expansion. Thefluid coke in this experiment represents a very small portion of thetotal mix-about 6 vol. percent in column 2 and about 12 vol. percent incolumn 3so it is surprising that the results obtained show no shrinkagein column 2 and some expansion in column 3. These data emphasize thefact that fluid coke behaves in a similar manner in all cementitioussystems but each system must be formulated depending on the type andamount of non-cement components.

Other obvious areas where fluid coke may be employed The addition of 50%fluid coke resulted in no expansion are reinforced concrete and moldedpanels.

SIEVE ANALYSIS F SOME COMMERCIAL FLUID (JOKES Percent Retained on SieveSieve Mesh 1 During sieving.

Fluid coke has the following characteristics:

Volatile matter (wt. percent on coke) at 1100 F. 0.5 to 1.3 Carbon (wt.percent) 88-93 Hydrogen (wt. percent) 1.5-2.0 Sulfur (wt. percent) 1-7Ash (wt. percent) 0.3-0.8

What is claimed is:

1. A dry Portland cement composition [which sets hard on standing anddoes not shrink when mixed with water in the ratio of about 6 to 614gallons of water per 94 parts by weight of Portland cement and allowedto set and] which contains between about 16.10 and about 132.68 parts byweight of fluid coke particles and between about 0 and 194.5 parts byWeight of sand per 94 parts by weight of Portland cement, said fluidcoke particles being less than 7 in size and mostly between about 20 and200 mesh.

2. A dry Portland cement composition [which sets hard on standing andwhich does not shrink when mixed with water in the ratio of about 6%gallons of water per 94 parts by weight of Portland cement and allowedto set and] which contains between about 16.10 and about 66.25 parts byweight of fluid coke particles per 94 parts by weight of Portlandcement, and between about 111 and about 194.5 parts by weight of sandper 94 parts by weight of Portland cement, said fluid coke particlesbeing less than in size.

3. A mortar mix composition including Portland cement, sand and fluidcoke particles in the following proportions, fluid coke to Portlandcement between about 33.19 and 63.84 parts by weight to 94 parts byweight of Portland cement, and between about 620 parts by weight and 563parts by weight of sand to 94 parts by weight of Portland cement.

4. A plastic composition which when mixed with water sets hard onstanding but which does not shrink on setting and which is useful formaking cement blocks, cement floors or walls, and reinforced concretestructures which includes an admixture of 1 part by weight Portlandcement with fine aggregate in an amount between about 0.1 to 4 parts byweight, coarse aggregate in an amount between about 1 and 6 parts byweight, water in an amount between about 0.3 to 1.0 by weight, and fluidcoke in an amount between about .1 and 3 parts by weight, the fluid cokebeing of a size predominantly in the range between about 20 and 200 meshand being the sole shrink counteracting ingredient.

5. A cement composition which when mixed with about 0.575 part by weightof water per part by weight of Portland cement sets hard on standing anddoes not shrink and which contains about 1 part by weight of Portlandcement, 0.8 part by weight of fluid coke particles smaller than 20 mesh,and 0.8 part by weight of delayed coke particles, the fluid cokeparticles being the sole shrinkcounteracting ingredient added to thecomposition.

6. A composition which comprises 1 part by weight of 10 Portland cement,0.8 part by weight of fluid coke particles and 0.8 part by weight ofdelayed coke.

7. A process for making a cementitious composition which comprisesmixing Portland cement with sand and fluid coke particles, said sandbeing in a weight ratio between about 13825 and about 79.0 to 94 partsby weight of Portland cement, and said fluid coke particles being in aweight ratio of between about 11.67 and about 51.21 to 94 parts byweight of Portland cement, said fluid coke particles being of a sizesmaller than about 34 8. A process for the manufacture of a concreteproduct which does not shrink on setting which comprises mixing 1 partby weight of Portland cement, between about 0.1 to 4 parts by weight ofsand, between about 1 and 6 parts by weight of coarse aggregate, fluidcoke particles in an amount of about 25 to 35 weight percent based onthe amount of Portland cement in the mixture, about 6 gallons of waterper pounds of Portland cement in the mixture, placing the mixture in amold and permitting the mixture to set and harden.

9. A process for making a mortar mix which will not shrink on settingafter being mixed with water and which comprises mixing Portland cement,lime and sand in proportions of 1-1-6 by volume and fluid cokeparticles, the amount of fluid coke particles being between about 6volume percent and 12 volume percent of the total mix.

10. An improved set concrete block made from a dry mixture which whenmixed with about 0.1 to 3 parts by weight of water sets withoutshrinking and which dry mixture includes 1 part by weight of Portlandcement, 0.1 to 4 parts by weight of fine aggregate, l to 6 parts byweight of coarse aggregate, and 0.1 to 3 parts by weight of fluid cokeparticles of less than 01 in size, said fluid coke particles being thesole added shrink-counteracting ingredient.

11. A cement block made from a plastic molded mixture which does notshrink upon setting and hardening, said plastic mixture containing about1 part by weight of Portland cement, about 0.1 to 4 parts by weight ofsand, about 1 to 6 parts by weight of coarse aggregate, about 0.3 to 1.0part by weight of water and between about 25 and 35 weight percent offluid coke particles based on the amount of Portland cement in saidplastic mixture, said fluid coke particles being of a size less thanabout 04 in diameter and being the sole shrink counteracting ingredientin the plastic mixture.

12. A cement block as defined in claim 11 wherein said fluid cokeparticles are mostly of a size between about 20 mesh and 200 mesh.

13. A set article formed from a wet plastic mixture which expands uponsetting and hardening, said wet plastic mixture containing about 1 partby weight of Portland cement, and about 1.6 parts by weight of fluidcoke particles, said fluid coke particles being of a size less thanabout 5 in diameter and being the sole expanding ingredient added to theplastic mixture.

14. A process for improving Portland cement compositions comprisingincorporating in said compositions fluid coke in an amount sufiicient toenable the compositions to set without shrinking or expanding.

15. A process for improving Portland cement compositions which comprisesincorporating in said compositions fluid cake in an amount sufiicient tocause expansion of the compositions upon setting.

16. A composition comprising Portland cement and fluid coke, said fluidcoke being present in an amount sufiicient to cause expansion of thecomposition upon setting.

17. A composition comprising Portland cement and fluid coke, said fluidcoke being present in an amount sufficient to enable the composition toset without shrink ing or expanding.

18. A composition for use in the construction industry and which, whenmixed with water, hardens and sets without shrinking, which includesabout I part by weight of Portland cement, about 1.1 to 9 parts byweight of mineral aggregate and 0.1 to 3 parts by weight of fluid cokeparticles of a size less than about 3/ 16", said fluid coke particlesbeing the sole shrink counteracting ingredient added to the composition.

19. A composition comprising Portland cement and fluid coke, said fluidcoke consisting of particles less than about 3/16 inch in size inamounts suflicient to lessen the shrinkage of said composition uponmixing with water and curing compared to the shrinkage occurring when anotherwise identical composition having the fluid coke replaced by anequal volume of fine aggregate is so cured.

References Cited The following references, cited by the Examiner, are ofrecord in the patented file of this patent or the original patent.

12 UNITED STATES PATENTS 1,772,149 8/1930 Jolitz 106-97 1,805,431 5/1931Ryder 106-97 2,609,882 9/1952 Morgan et al. 106-97 5 2,881,130 4/ 1959Pfeiifer et a1 208-157 3,102,039 8/1963 Manecke 106--97 FOREIGN PATENTS4632/1894 1/ 1895 Great Britain.

TOBIAS E. LEVOW, Primary Examiner.

W. T. SCOTT, Assistant Examiner.

15 us. 01. X.R.

